Hard water soluble oil



May 5, 1936- E. w. ADAMS Er A1. 2,039,377

' HARD WATER soLUBLE OIL Filed May 20. 1933 l .O f s 1 o a 55 s Q) ."5 Q S l n) L EQ Q .S 3S. E \\g cg Q m N QQ sorge NFLint Y, B/M// 4;

Patented May 5, 1936 UNITED STATES PATENT oFFVlcE 2,039,311 man WATER soLUBLE on.l

Elmer Wade Adams, Hammond, Ind., and George W. Flint, Chicago, Ill., assignors to Standard Oil Company, Chicago, lll., a corporation of Indiana Application May 20, 1933, Serial No. 672,050

3 Claims.

fying agents so that when they are poured into water they immediately form stable emulsionsv without necessity of special dispersing means, which are suitable for use as cutting oils,` drawing oils, textile or wool oils, tree sprays, lubricants, coal sprays, antirust oils or any other use for which soluble oils are usually employed.

A large variety of substances have been used in the manufacture of soluble oils, particularly fatty acid soaps, naphthenic soaps, sulfonic soaps, oleic acid, sulfonated compounds, etc. In most of these soluble oils it has been necessary to use a small amount of alcohol for obtaining the desired surface tension characteristics, for stabilizing the soluble oil against low temperatures and for improving the dispersion of the soluble oil on admixture with water. The use of alcohol is objectionable not only because of its expense, but because it tends to evaporate from the nished product and it thereby causes deterioration prior to use. An object of our invention is to provide a soluble oil which does not require the use of alcohol.

Most soluble oils are quite satisfactory with ordinary soft waters but they cannot be satisfactorily used in hard waters because the calcium and magnesium compounds upset the delicate balance between interfacial tensions which is necessary for satisfactory emulsiiication. An object of our invention is to provide a soluble oil which will produce excellent emulsions in extremely hard water which will not cream and separate oil on standing, as a result of insuicently small particle size.

A further object of our inventi'on is to provide a highly eicient soluble oil employing mahogany soap, soda rosin soap or its equivalent, and an amount of water which is just suilicient to produce an excellent emulsion but is insufficient to cause the separation of soaps from the oil, during storage, in transit or prior to actual use. Other objects of the invention will be apparent from the following detailed description.

It has long been known that mahogany soap (preferentially oil soluble mineral oil sulfonates) has the propertyl when dissolved in oil, of lowering the surface tension of the oil and thereby promoting the emulsiiication of the oil in water .(see Petroif 1,230,599). vIt hasv always been necessary to supplement this mahogany soap with a Water-sol# uble soap and with small amounts of alcohol. We have discovered that by careful purifying or fractionating the mahogany soap, and by carefully regulating the proportions of this improved material with soda rosin soap or its equivalent we may eliminate the use of alcohol entirely and at the same time obtain the soluble oil which is extremely stable at very low temperatures, which is noncorrosive and which, when poured in water, gives an emulsion which does not readily separate out even with the hardest waters. f

'The preferred formula for our improved soluble oil is about as follows:

The mahogany soap may in general be -prepared as described in the United States patent to Humphreys, No. 1,286,179, in the manufacture of white oils, medicinal oils and the like. Mineral oils are treated with a number of dumps of concentrated or fuming sulfuric acid, and the resulting sludge is separated from the oil after each dump. The so-called green acids are'separated with the sludge and withdrawn, and the preferentially oil-soluble sulfonic acids remain dissolved in the oil. These acids are neutralized to form soaps and the soaps are extracted with 50% aqueous alcoholic solutions. These so-called mahogany soaps contain considerable amounts o f oil. They also contain considerable amounts of sodium sulfate which is either dispersed or dissolved, or may be in chemical combination with the mahogany soap, since it remains in the oil phase when the green acid soap and sludge are separated. The sodium sulfate may be removedfrom the mahogany soap by further extraction with concentrated alcoholic solutions, as'disclosed in United States Patents 1,493,111 and 1,708,838. When the mahogany soap is extracted with 80% alcohol, we find that this concentrated alcoholic solution not only removes impurities such as sodium sulfate, but that it tends to further fractionate the mahogany soap itself, and we have found that the purified mahogany soap remaining dissolved has new and unexpected properties when employed in soluble oils in the manner described.

The soda rosin soap may be prepared in the conventional manner and it maybe replaced in our formula by A any other equivalent water-soluble soap. We prefer to use a relatively light mineral oil, for instance, one having a viscosity between 80 and 300 seconds at.A 100 F. The oil may have received any degree of renement by conventional acid treatments, solvent extraction treatments, claying treatments, etc., the type of oil used depending primarily upon the use for which it is designed.

The process of manufacture is as follows: The

mahogany soap is first puried by mixing one part of e soap with one and one-half parts of 'Z8-80% (by volume) alcohol. The twoare thoroughly mixed at -150o F. and then cooled to 00 Fxor/low'er. .After settling, the solution of light colored soap is separated, the nal product CFI 'The' puried mahogany being freed 'fro'm alcohol'and designated as puriedmahogany soap.

soap and soda rosin so'apare-heated and agitatedin a mixer in the proportions hereinabove setforth. The heating ner may be cooled to extremely low temperatures and may be stored in an iceboxfor days without i 'separating out or becoming cloudy. When this oil i's added towater, even if the. water is exaoeaav? hours, in anice boxmaintained at aboutz40-45 F.

A remarkable feature of our improved soluble oi1 is the factthat it forms an. immediate permanent emulsionwith extremely hard water.

lion, and la total hardness therefore of -53 8 parts trexnely hard, it immediately emulsifies vwithout v .the separation of any 'oil at the surface.

salts-from soluble cils or this general type. We

'7 have -found that the emulsibility f an oil ismaterially lowered bythe presence of s'alts. A series of oils were made by adding various amounts of a salt (N azSOi). solution-of known concentrationv to the oil, drying the oils and bringing them back to approximately the same water content.. The eiect of the'ssalt on emulsibility is'shown by the following liable;

. E uivm Emulsibimy Percent cc. salt Percent legt salt original solution salt in in soap salt added oil Stock .In cold In cold tap water hard wat-cr o. 24 ,o o 24 1.00 Excellent Excellent 0.24 1 0. 40 1.66 Excellent Good 0. 24 2 0.56 2. 33 Excellent N0 [lood 24 3 0.- 72 3. 00 No goodl No good 0.24 4 0.88 3.66 No good 0l24 5- 1.04 4.33 -Nogood We have found that theA salt content in our mahogany soap stock (50% soap) mustI be main-l tained as near to one percent or below as is possible, determined by the following method: The ether solution of mahogany soap and oil is washed mineral' acid solution is saved, dried and weighed.

From this weight 4the sodiumchloride formedi from the decomposition o f the soap and calculated from the titration of the acid is deducted.

Even whenthehighly purified 'orfractionated j 'From the above specific examples and from the m'ahoganysoap 'is' used a's the basic emulsifying -agent it is still necessary to4 carefully regulate the proportions of Water-soluble Vsoap' and water if t'heresultingsoluble. o il is to pass all.specica tions without the use of alcohol.

n The purified mahogany soapcontent-may vary over relatively vwide ranges-but it should not go below about 8%, v andY f or practical purposes it will not be above` 40%. An increase in the mahogany soap content permits a decrease in the mahogany-rosin soap ratio and/or an increase inthe wate'r content.

In general, an increase in oil viscosity requires'l aslight increase in total ,'emulsifying' agent.A

With 'a-mahogany soap contentoi 12% the soda from the oi-l at low temperatures. vvThe soluble oil should show n o' separation of water' and emulsifying agent afterlongl standing,-at least. 48

purified mahogany soap is as follows:

per. million (calculated as calcium carbonate).

In order to have a standard of comparison, a

hard water is used-for testing emulsibility. About 0.2718' grams 2CaSO4-Hz0, 0.2540 grams MgSO4.'

Our improved solu'bie` oils emulsify-readily andl give suitable emulsions in thisextremely hard water.

Another characteristic of our product isv the extremely high'degree of dispersion it gives vWhen mixed with water. The drawing shows in graphical form the results obtained with such an emulsion. The-differential ratio of concentration and radius is plotted against the' particle size from which it is seenthat mostof the particles fall within thejra'ngeof 30millimicrons or smaller.

T his' unusually small particle size we believe accounts for the great stability of .this emulsion.

Hereinabove we have given a. preferred formula employing 12% mahogany soap. Another preferred embodiment using a4 larger amount of Per cent Puriiied mahogany 'soap stock (50% soap)- 35 Junior red engine oil 61 I In making o ur soluble oil on a commercial scale 'it is sometimes convenient to employ a puried mahogany soap in admixture with 'about 50% 'of l oil, and it is also'convenient to apply a soda rosin soap stock containing of water.. Thus a prevdients, usingferredforfmula might be made with these ingre- (80 sec. vis. at.100 F., '359 F. pour, 1-2 NL P.A.

` color) general principles hereinabove set forth it will be seen that'the'I proportions of puried mahogany soapto water-soluble soap and/or. water must be carefully regulatedbut can be readily determined in accordance withl the principles hereinabove stated. We vdo not limit ourselves Vto any of the specic .details hereinabovedescribed except as defined bythe following claims which should be construedasbroadlyas the prior art will permit.

fWe claim;

1 ;A soluble oil which contains lno alcohol and,

which willreadily emulsifyin extremely hard water and which consists essentially of a mineral about 8% to 40% of puriied mahogany soap, a

small amountl of a preferentially water-soluble of water beingsuiciently low to prevent separasoap, Aand about2 .5% to 0.5% of water, the amount 2,039,377 o he soap when the soluble oil is exposed 3. A hard water soluble oil having about 'the of t g1g-nan extended period to an ice bath. following formula:

2, A hard water soluble oil having about the Per cent following formula: Purified mahogany soap (oil free) 12 5 f Pel' cent Soda. rosin soap (dry) 2.5 5 i Purified mahogany soap (soluble in 80% Water 1 5 31601101) 8-40 Mineral nn 34.0 Y Soda rosin soap 1-6 Water. 2.5-0.5 ELMER WADE ADAMS. 10 Lubricating oil balance to 100 GEORGE W- FHNT- 10 

